CVE-2026-109363

HIGHCVSS 7.5

Description

ZcashFoundation Zebra 6.4.0 before 6.4.2 parses version 6 transactions carrying a pre-NU6.3 consensus branch ID, but the size computation during UnminedTx construction treats re-serialization of the Orchard bundle as infallible, so the resulting error trips an expect that aborts zebrad. Unauthenticated peers can send a single pre-handshake tx message to crash the node, and can repeat this after each restart.

Timeline

Published:October 12th, 2026 5:17 PM

Last modified:October 15th, 2026 8:31 PM

CVSS Scoring

CVSS v3: 7.5 (HIGH)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-617

References & Reports

Advisories, patches, and third-party reports

https://github.com/ZcashFoundation/zebra/commit/008abac5c99e872f283450d596d95e37851df49a
https://github.com/ZcashFoundation/zebra/security/advisories/GHSA-h5rr-8pqv-grp9
https://www.vulncheck.com/advisories/zebra-6.4.0-before-6.4.2-denial-of-service-via-malformed-v6-transaction

Source: NIST NVD · Data may lag official sources by up to one minute